Chemicals, plastics and rubber industries

Etching of GaAs(100) surfaces by halogen molecules: density functional calculations on the different mechanisms

Article Abstract:

Reaction energies and partially, related barrier heights are calculated for the chemisorption / desorption of X2, Ga2, GaXn, and AsXn (n = 1-3, X = F, Cl, Br, and I) from halogenated GaAs(100) surfaces modeled by molecular clusters by employing density functional theory. The findings of the study indicate that under high halogination, strongly bound GaX2 and AsX2 and weakly bound GaX3 and AsX3 are found at the surface and volatility increases for GaX3 from F to I.

Etching of GaAs(100) surfaces by Cl2: Quantum chemical calculations on the mechanisms

Article Abstract:

Quantum chemical calculations were executed with molecular models of local structures of flat surfaces and steps with various chlorinations, for the interpretation of experimental findings and the development of concrete mechanisms of the GaAs etching by chlorine. The stability and the reaction behavior of free and low chlorinated surfaces are investigated with (4*2)-dimer models.

Local structure around chloride ion in anion exchange resin

Article Abstract:

Various studies are conducted to analyze the local structure around the chloride ion adsorbed in an anion exchange resin. The analysis reveals that any direct interaction between chloride and any other ion reduces the number of first-neighbor water molecules around chlorine.